Advanced motor grader controls

ABSTRACT

A motor grader control arrangement uses a joystick control arrangement to control the operating functions of the motor grader. Two joystick controllers are provided on opposite sides of an operator&#39;s chair and the most convenient movement of each joystick controller, for example, fore-aft, side to side, and right and left rotation, are assigned to the most common grader adjustments. Each controller also includes an offset control surface with a series of thumb actuated press buttons for adjusting a given hydraulic component in a positive or negative response. The forward face of each joystick controller can include finger actuated press buttons. The distribution of the control functions between joystick controllers maintains similar activity to void operator fatigue in one hand. This also provides better operator control.

FIELD OF THE INVENTION

[0001] The present invention relates to motor grader controls, and inparticular, an improved control arrangement which uses right and lefthand joystick controllers.

BACKGROUND OF THE INVENTION

[0002] Operation of a motor grader requires considerable skill due tothe number of hand operated controls and the general complexity ofmotion associated with the various implements of the vehicle. Thedifficulty in achieving a satisfactory level of control is furthercompounded as the actuation direction of the traditional control leversof the vehicle is not necessarily aligned with the desired motion to beimparted to the actual implement. For example, the control lever couldbe a fore aft direction of movement for extending or contracting a sideshift cylinder in basically a side to side direction. The fore aftmovement of the lever has no direct correspondence to the movement ofthe actuator.

[0003] A motor grader due to its particular application and complexityhas a host of different controls and requires extensive experience tobecome efficient.

[0004] As a result of the complexity of the machine and the numerouscontrols, the operator learning curve is long and relatively shallow. Inaddition, the previous controls have forced the operator to move hishands between different types of controls and actually release onecontrol to move a different control.

[0005] There have been numerous proposals to simplify the controls andoperation of a motor grader. United States Statutory InventionRegistration H1, 831 discloses two joystick controllers for controllingthe function of a motor grader. These joystick assemblies control theblade, the vehicle drive and the steering system of the vehicle.Attempts have been made to make the direction and motion of the controlsmore compatible with the implements that they control. Although it isrecognized that a better control for a motor grader is required, thestructure disclosed in the Statutory Invention Registration is quitecomplex and has not been readily accepted.

[0006] The present invention provides an improved control arrangementwhich overcomes a number of the difficulties described above.

SUMMARY OF THE INVENTION

[0007] The motor control arrangement according to the present inventioncomprises an operator seating position with a right hand joystickcontroller and a left had joystick controller mounted on opposite sidesof the seating position. Each joystick controller controls a pluralityof operating functions of the motor grader and each joystick is movablein a fore and aft direction, a side to side direction, and a right andleft horizontal rotation. This provides six control functions.

[0008] Each joystick controller further includes a series of thumbactuator buttons with the buttons being paired and each pair controllinga hydraulic component. Actuation of one button of the pair causing afirst direction of movement of the hydraulic component and actuation ofthe other button of the pair causing an opposite direction of movementof the hydraulic component.

[0009] According to an aspect of the invention, the hydraulic componentscontrolled by the joysticks include any of hydraulic cylinders,hydraulic motors, hydraulic valves and hydraulic actuators.

[0010] According to a further aspect of the invention, each joystickcontroller includes an enlarged inwardly extending control surface andthe series of buttons are located on the control surface.

[0011] According to yet a further aspect of the invention, each pair ofbuttons on the control surface has a unique textured surface associatedtherewith.

[0012] According to yet a further aspect of the invention, the uniquetextured surface associated with each pair of buttons is an elongateregion, which extends between the respective buttons.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Preferred embodiments of the invention are shown in the drawings,wherein:

[0014]FIG. 1 is a side elevational view of a motor grader with variouscomponents thereof;

[0015]FIG. 2 is a perspective view of the joystick control arrangement;

[0016]FIG. 3 is a rear view of one of the joystick controllers;

[0017]FIG. 4 is a front view of the controllers; and

[0018]FIG. 5 shows distinctive shapes applied to the button actuators.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] The motor grader 2 has a rearwardly extending draw bar 3 attachedto the front of the frame 4 with a high lift arrangement 6 supportingthe rear of the draw bar. The grader blade 7 is supported below the drawbar and is rotatable about a vertical axis to change the angle of thegrader blade 7 beneath the grader. The grader blade 7 is also slidablelongitudinally beneath the draw bar and is tiltable in the fore aftdirection to change the cutting angle.

[0020] The rear portion of the draw bar is movable beneath the graderframe from side to side of the motor grader by means of the side shiftcylinder 5. High lift cylinders 10 control the position of the graderblade and move it from the raised position of FIG. 1 downwardly to aground engaging position.

[0021] An operator controls the grader from within the cab 15. Therehave been a host of arrangements for controlling the motor of thegrader, the transmission of the grader, the articulation of the grader,the lean of the front wheels of the grader, the steering of the frontwheels of the grader, and a series of controls associated with thegrader blade 7. Recently, it has been proposed to control the mainoperating functions of the grader, namely the various controlsassociated with the grader blade, and the steering and propulsionfunctions of the grader using joystick controllers provided at anoperating station within the cab 15. The control arrangement 20 shown inFIG. 2 provides a significant advance and provides an ergonomic as wellas intuitive control arrangement for the motor grader. The arrangementincludes a left hand joystick controller 30 and a right hand joystickcontroller 32.

[0022] The following functions are controlled by the left hand joystickcontroller 30 and the right hand joystick controller 32. Thesecontrollers are positioned either side of the operator seating positiongenerally shown as 34. The blade lift or height of the blade iscontrolled by the hydraulic lift cylinders 10 provided either side ofthe motor grader. The left blade lift cylinder is controlled by the foreaft movement 36 of the left controller 30. The right blade lift cylinderis controlled by the fore aft movement 38 of the right hand controller32. Forward movement of the joystick controller causes the respectivecylinder to lower and rearward movement of the controller causes therespective cylinder to lift the blade. This is the conventionaldirection of movement associated with the traditional series of controllevers that grader operators are familiar with. These functions are themost often used of all of the blade controls and are the most importantwith respect to response time and accuracy. The controller channelsassociated with these movements are fully proportional in that theactuation of the hydraulic valve from the movement of the handle isaccurate and is also designed electronically for precise proportionalresponse based on movement of the respective joystick controller.

[0023] Steering of the wheels of the grader is controlled by the side toside movement 40 of the left hand controller. Left movement causes thewheels to steer left and right movement causes the wheels to steerright. This steering control is also fully proportional to allow theoperator to control the grader in an efficient and time responsivemanner.

[0024] Wheel lean of the front wheels is typically used for offsettingblade side loads. Basically, an angled blade can transfer a significantside load to the grader and leaning of the front wheels can assist inproviding an efficient offsetting load. Left hand movement of the righthand controller causes the wheels to lean to the left and right movementcauses the wheels to lean right. The wheel lean control movement isindicated as 42. This function is also fully proportional. It should benoted that a return to the neutral position maintains the lean that hasbeen imparted to the wheels. If the wheels are to be returned to a morevertical position, then the joystick needs to be moved in the oppositedirection.

[0025] The blade of the motor grader is supported on a very largerotatable gear, rotatably supported beneath the draw bar of the grader.This is commonly referred to as the circle turn. The rotation of thecircle turn is controlled by rotating the left hand controller about itsvertical axis as indicated by the movement 44. Rotation of the joystickcontroller in a clockwise manner moves the circle clockwise. Twisting ofthe handle of the controller in a counterclockwise direction moves thecircle in a counterclockwise manner. This function is a simple on/offelectronic control as the circle rotates slowly and therefore, can becontrolled accurately without proportional electronics.

[0026] Articulation of the motor grader frame is also a function that issomewhat unique to a motor grader. Basically, the frame 4 of the motorgrader is pivoted about a vertical axis at position 19 (FIG. 1) and thefront wheels of the motor grader can be offset to either side of thetandem drive. Articulation of the grader frame is controlled by twistingthe handle of the right hand controller about its vertical axisindicated as 46. Twisting the handle clockwise offsets the frame to theright or clockwise, and twisting the handle counterclockwise offset theframe to the left. Once again, this is a simple on/off function and istypically an adjustment that is completed relatively slowly. The righthand joystick controller controls the ability to articulate the graderframe once it has been released.

[0027] A motor grader also has the ability to allow the blade to float.Blade float allows the lift cylinders to move freely up and down as theblade follows the contour of the ground or road. This operation isinitiated by double clicking the respective triggers 48 and 50 on thefront of the left and right hand, pressing the trigger twice within apreset time limit, typically in the order of one second. Doubleclicking, pressing the trigger twice within a short time period allowsthe respective lift cylinders to float. Moving the left handle, forexample, in the fore aft direction such as to directly control the leftlift cylinder will result in the termination of the float feature andreturn to normal control. Thus the triggers 48 and 50 allow activationof the respective float feature of the lift cylinders. Thus, eachjoystick controller controls the respective lift cylinder float feature.

[0028] Blade tilt is controlled by the two left most buttons 52 and 54on the rear or operator side of the left hand joystick. The upper button52 when depressed will cause the blade to tilt forward. The lower button54 when depressed will cause the blade to tilt rearwardly.

[0029] Each pair of buttons on a joystick controller preferably has aunique shape which is recognizable by touch. In this way, the operatorcan confirm without visually confirming his hand position that thecorrect button actuator is being engaged. Several different top surfacesof the buttons are shown in FIG. 5. In this case, one of the buttons hasa projecting top surface, one of the buttons has a recessed grid topsurface, and one button has a concave top surface. Other distinctiveshapes and top surfaces can be used.

[0030] A motor grader also has the capability of having a series ofdifferent attachments mounted to the front of the grader. Typicalattachments include a bulldozer blade type attachment and a snowplowattachment. The raising and lowering of the equipment is controlled bythe two center buttons 56 and 58 on the rear or operator's side of theleft joytstick controller handle. The upper button 56 when depressedwill lower the attachment. Depressing the lower button 58 will raise theattachment; double clicking the upper button within a specified timeperiod will float the front attachment. Activating either button againwill disengage the float and return to the raising and lowering controlsto the buttons.

[0031] A ripper or scarifier can be attached to the grader and is atoothed attachment used for tearing of a surface. There are certaintypes of rippers, which are attached to the rear of the motor grader,and there are other rippers secured behind the front axle of the motorgrader. The raising or lowering of this equipment is controlled by thetwo right most buttons 60 and 62 on the rear or operator's side of theleft controller handle. Depressing the upper button 60 will lower theequipment and depressing the lower button 62 will raise the attachment.

[0032] Motor graders are also used for snow plowing. In some cases, asnow wing is attached to one side of the grader for this particularfunction. The snow wing includes a forward mast and a rearward mast forraising and lowering of the snow wing. The front of the left controlleris equipped with two buttons. The upper right button when depressedraises the front wing mast. The lower left button when depressed willlower the front wing mast.

[0033] The two lower most buttons 66 and 68 on the rear or operator'sside of the right hand controller operate on the snow wing lift.Depressing the right button 68 causes the wing to lower or displaceoutwardly to the right. Depressing the left button 66 causes the wing toraise or displace inwardly to the left.

[0034] The snow wing also includes a rear snow wing mast. The frontsurface 51 of the right controller 32 is equipped with two buttons 70and 72. Depressing the lower right button 72 will lower the rear mast.Depressing the upper left 70 button will raise the mast.

[0035] As previously described, the grader blade 7 is also slidablebelow the circle gear. The two upper most buttons 74 and 76 on the frontface of the right hand joystick controller operate the blade slide.Depressing the right button 76 causes the blade to slide to the right,depressing the left button 74 causes the blade to slide to the left.

[0036] The position of the rear of the drawbar 3 is controlled by theside shift cylinder 5. The two center buttons 78 and 80 on the frontface of the right hand joystick controller 32 operate the circle sideshift cylinder. Depressing the right button 80 causes the drawbar to bedisplaced to the right and depressing the left hand button 78 causes thecircle to displace to the left.

[0037] As can be appreciated, the operator controls the speed of thegrader and the transmission of the grader. The left hand controller 30is equipped with a three position rocker switch 82 with a small lockbutton. The switch, when rocked forward will place the transmission inthe forward range. Rocking the switch rearwardly or downwardly willplace the transmission in reverse. When the switch is in the center orneutral position, the transmission is in neutral. The lock button on therocker switch prevents the switch from moving from the center positionuntil the lock button is depressed and the switch moved into the desiredposition.

[0038] Transmission gear control is provided on the right handcontroller 32. The controller has a three position momentary rockerswitch 84 with a small lock button. The switch when rocked rearwardlywill down shift the transmission. Rocking the switch in the oppositedirection causes an up shift of the transmission. The lock button on therocker switch prevents the rocker switch from moving from the centerposition until the lock button is depressed and the switch is rockedinto the desired position.

[0039] Additional functions can be added to the control arrangement asrequired.

[0040] Turning to FIGS. 3 and 4, it can be seen that the joystickcontrollers have a grip portion 100 with a paddle or control portion 102thereabove. The various buttons are provided on the control portion 102and this area has also been textured about button pairs to allow theoperator to recognize where his thumb is located for actuatingappropriate buttons. As shown in FIG. 4, the left hand controllerincludes three unique textured areas 51, 53 and 55. Similarly, righthand controller 32 has unique textured areas 57, 59 and 61. The controlbuttons can also be shaped, colour coded or paired to provide a visualindication. The most frequently used controls are associated with thethree way action of the joystick controllers. This is particularly truewith respect to the fore and aft direction of the joystick controllerand the side to side direction of the control stick of the controllers.

[0041] The stick portion or grip portion of the controller is alwaysmaintained in the operator's grasp and his thumb is primarily used forselecting of the various button controls. Some control buttons areprovided on the front surface of the control portion 102 (See FIG. 3)and these can be actuated using one or two of the fingers of theoperator. As can be appreciated, there is extensive movement anddexterity capabilities with respect to the operator's thumb and thisprovides easy control.

[0042] In the present design, the control functions of the motor graderhave been divided or distributed such that each hand of the operatorbasically shares the numerous operating movements required to controlthe grader. In this way, each hand is active and one hand is notextensively overloaded. Consideration has been given to assigning thecontrol functions in a logical, intuitive manner without overloading anyone hand. Maintaining each hand active reduces hand and arm strain andreduces operator fatigue. In addition, better control of the grader isprovided due to the sharing of the workload. The convenient layout andthumb and finger actuation allows easy transfer between graderfunctions. Control of two functions simultaneously, is also practical aseach hand functions independently.

[0043] Although various preferred embodiments of the present inventionhave been described herein in detail, it will be appreciated by thoseskilled in the art, that variations may be made thereto withoutdeparting from the spirit of the invention or the scope of the appendedclaims.

1. A motor grader control arrangement comprising an operator seatingposition with a right hand joystick controller and a left hand joystickcontroller mounted on opposite sides of said seating position, eachjoystick controller controlling a plurality of operating functions ofthe motor grader, each joystick controller being movable in a fore aftdirection, a side to side direction and a right and left horizontalrotation and thereby control six functions, each joystick controllerfurther including a series of thumb actuated buttons with said buttonsbeing paired and each pair controls a hydraulic cylinder with one buttonof the pair causing a first direction of movement of the hydrauliccomponent and the other button of the pair causing an opposite directionof movement of the hydraulic component.
 2. A motor grader controlarrangement as claimed in claim 1 wherein said hydraulic componentsinclude any hydraulic cylinders, hydraulic motors, hydraulic valves andhydraulic actuators.
 3. A motor grader control arrangement as claimed inclaim 1 wherein each joystick controller includes an enlarged inwardlyextending control surface and said series of buttons are located on saidcontrol surface.
 4. A motor grader control arrangement as claimed inclaim 3 wherein each pair of buttons on said control surface have aunique textured surface associated therewith.
 5. A motor grader controlarrangement as claimed in claim 4 wherein said unique textured surfaceis associated with an elongate region of said control surface extendingbetween the respective buttons of the pair.
 6. A motor grader controlarrangement as claimed in claim 3 wherein said inwardly extendingcontrol surface is of a curved exterior shape.
 7. A motor grader controlarrangement as claimed in claim 6 wherein said control surface forms apaddle shaped extension of said joystick controller.
 8. A motor gradercontrol arrangement as claimed in claim 7 wherein some of said pairs ofbuttons are positioned on said control surface in a generally side byside relationship and some of said pairs of buttons are positioned onsaid control surface in a generally top bottom relationship.
 9. A motorgrader control arrangement as claimed in claim 2 wherein at least one ofsaid joystick controllers includes one of said pairs of buttons on arear surface of said joystick controller.
 10. A motor grader controlmanagement as claimed in claim 1, wherein one of said joystickcontrollers, controls steering of front wheels of the grader by a sideto side pivotting movement, and side to side movement of the otherjoystick controller, controls wheel lean of the grader.
 11. A motorgrader control arrangement as claimed in claim 1, wherein the controlfunctions of the grader are assigned to said joystick controllers in amanner to distribute the workload therebetween such operation of thegrader each hand of the operator is active.
 12. A motor grader controlarrangement as claimed in claim 3, wherein said series of buttons arepairs of buttons, and said pairs of buttons on each joystick controllerhave a different shape distinguishable by touch.